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[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
A Lewis Base Catalysis Approach for the Photoredox Activation of Boronic Acids and Esters
Fabio Lima1, Upendra K Sharma2, Lars Grunenberg1
1Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK.
Abstract:
We report herein the use of a dual catalytic system comprising a Lewis base catalyst such as quinuclidin-3-ol or 4-dimethylaminopyridine and a photoredox catalyst to generate carbon radicals from either boronic acids or esters. This system enabled a wide range of alkyl boronic esters and aryl or alkyl boronic acids to react with electron-deficient olefins via radical addition to efficiently form C-C coupled products in a redox-neutral fashion. The Lewis base catalyst was shown to form a redox-active complex with either the boronic esters or the trimeric form of the boronic acids (boroxines) in solution.
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